Which nonfictional documentaries about Artificial Intelligence are available?
AlphaGo (2017) is quite a good watch, given that it is a documentary about the AlphaGo program, how DeepMind developed it, the help they had, and doesn't get too technical.  You can watch the trailer here.

Another documentary which wasn't exactly AI but something that is an interesting watch or at least was when it came out was The Human Face of Big Data.